Deadlatching lock



Feb. 15, 1966 M. M. CHECK 3,235,298

DEADLATCHING LOCK Filed Jan. 16 1963 n 2 Sheets-Sheet 1 Q INVENTOR. MA fH/AS M Cmrck Afro/ way Feb. 15, 1966 M. M. CHECK DEADLATCHING LOCK 2 Sheets-Sheet 2 Filed Jan. 16, 9 3

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INVENTOR. MAT/{I46 M Cmsck United States Patent O 3,235,298 DEAIELATCIIING LOCK Mathias M. Check, Strafford, Pa., assignor, by mesne assignments, to Yale & Towne, Inc., New York, N.Y., a company of Ohio Filed Jan. 16, 1963, Ser. No. 251,934 Claims. (Q1. 292-5) This invention relates to a novel deadlatching lock for a door.

The locks of the particular class are equipped with means that act automatically when the door closes to deadlock a spring-pressed latchbolt. Thus, there is a trigger bolt that will be held retracted by a strike, causing mechanism in the lock to dog the latchbolt in projected position, as will be understood. The locks naturally have means that will undog the latchbolt when it is to be retracted by a knob or key. The earlier locks of this kind generally operate very well. In some cases, however, it has been difficult to design an effective deadlatching mechanism, due largely to the fact that some locks leave little room available for the mechanism and its trigger on the lock casing. The novel concept of my invention is a deadlatching mechanism that will require very little space on the lock casing, while contributing exceedingly satisfactory deadlatching operation.

In my novel construction, I arrange a trigger bolt to move within the outlines of the same opening in which a latchbolt moves on the front of a lock casing. The trigger bolt has a thin section, and by slightly reducing the section of the latchbolt, both bolts may be mounted in an opening of standard size. In the form that I prefer, the trigger bolt is a plate which is assembled in juxtaposed relation to the top or bottom surface of the latchbolt.

The thin trigger bolt has an end portion that will extend beyond the outline of the front opening in the lock casing, it being obvious that the opening need not be designed to accept the end portion of the trigger bolt. Thereby, the trigger bolt is so shaped that it will not enter the opening into which the latchb-olt moves in the strike, even though that also is a standard opening. I am aware that the prior art has attempted to use trigger bolts that are quite narrow, but I have found that those earlier bolts sometimes will not operate properly because they may move with the latchbolt into the strike opening. When that happens, the bolts may even become so wedged in the strike that it is impossible to retract the latchbolt. The trigger bolt of my novel lock will not enter the strike opening, even when made extremely thin. It may in effect he said that my trigger bolt will operate in the manner that is required, while taking up no more room on the lock than does a standard latchbolt.

My invention further utilizes a simple dogging plate that will require little space in the lock casing. That plate is arranged in juxtaposed relation to an inner side of the lock casing, and is controlled through a cam relation to the trigger bolt and to a bolt retracting part, being so pivoted that it need move only a short distance to a dogging position behind the latchbolt.

The lock that I actually show in this application is constructed with features like those which form the subject of the earlier application of Paul P. Kubik, Serial No. 104,913, filed April 24, 1961, now Patent No. 3,115,357. Thus, there are a deadbolt and a latchbolt, and means that are manually actuated by the occupant of the room for deadlocking both bolts. The features of my present invention enable me to achieve that kind of locking together with automatic deadlatching, so that in effect I contribute double deadlocking of the latchbolt.

My invention will enable me to manufacture a series of locks at relatively low cost. Thus, my trigger bolt is ice adapted to be mounted in a standard opening in a lock casing, and few changes need be made in the lock in order to equip the lock with my deadlatching mechanism. Actually, it will be possible to utilize lock parts that are standard in nearly all respects, whether or not the lock is to have a deadlatching function.

I have thus outlined rather broadly the more inportant features of my invention in order that the detailed description thereof that follows may be better understood, and in order that my contribution to the art may be better appreciated. There are, of course, additional features of my invention that will be described hereinafter and which will form the subject of the claims appended hereto. Those skilled in the art will appreciate that the conception on which my disclosure is based may readily be utilized as a basis for the designing of other structures for carrying out the several purposes of my invention. It is important, therefore, that the claims be regarded as including such equivalent constructions as do not depart from the spirit and scope of my invention, in order to prevent the appropriation of my invention by those skilled in the art.

In the drawings:

FIG. 1 shows my novel deadlatching lock mounted on a door;

FIG. 2 shows a longitudinal section of my lock taken on the line 2-2 in FIG. 3;

FIG. 3 is a section on the line 3-3 in FIG. 2;

FIG. 4 is a section showing parts of my lock in dea latching position;

FIG. 5 is a vertical section showing the double deadlocking position of my lock;

FIG. 6 shows a perspective view of parts of my lock.

For the purpose of describing my invention, I have chosen to show in the drawings a lock construction which is much like that shown in Patent No. 3,115,357 to which I have already referred. Thus, referring particularly to FIG. 1, I show a lock casing 10 that is adapted to be inserted in a rectangular notch formed in the edge of a door D, and that supports a pair of inside and outside knobs 11 and 12. At least the inside knob 11. can be rotated for retracting a spring pressed latchbolt I3 relatively to the front 14 of casing Iii. The outside knob 12 may be fixed as in the patent, but conceivably may be a rotatable knob that can be locked. There is an inside finger piece 15 that will be rotated to project and to retract a deadbolt 16, and that is effective for dogging both bolts 13, 16 in projected position. I may call attention to the fact that the front area 14 of lock casing lil is rather small, and that the latchbolt I3 and deadbolt I6 fill a very large part of that area. However, in my present invention, I also arrange on the front 14 a trigger bolt 17 which will effect deadlatching of the latchbolt 13, as I shall fully describe.

Referring in more detail to FIG. 3 of the drawings, the latchbolt I3 is mounted on a pivot pin 19 so as to rotate between projected and retracted positions relatively to an opening 18 in the front 14 of the lock casing. Latchbolt 13 has a rather usual shape with a bevelled side 20 adapted to move against a strike 21, FIG. 4, so that the strike will retract latchbolt 13 as the door moves toward closed position. A curved side 22 on latchbolt 313 will enter an opening '23 in the strike 21 when the door is fully closed, as will be understood.

In the deadlatching construction that I have new conceived, the trigger bolt 17 has a relatively thin plate-like shape, FIGS. 2, 5 and 6, and is arranged within the outlines of the same opening 18 in which latchbolt 13 moves. I prefer to mount the thin trigger bolt 17 in juxtaposed relation to the bottom surface of latchbolt 13, as viewed in FIG. 2, for rotation between projected and retracted positions on the same pivot pin 19 as does latchbolt 13.

3 As best seen in FIG. 4, I utilize a U-shaped spring 24 having opposed ends engaged in openings in the lock casing and in a rear portion of trigger bolt 17, whereby to press that bolt toward projected position.

I form the plate-like trigger bolt 17 with an inclined forward side which continues in a radial direction to an end portion 26 that lies beyond the curved side 22 of latchbolt 13. When the door is in closed position, as in FIG. 4, the end portion 26 will engage a surface 27 at one side of opening 23' on the strike 21. Thus, I actually am able to make the trigger bolt 17 very thin, yet that bolt 17 will be held retracted by strike 21 and will not project with latchbolt 13 into strike opening 23. The strike 21 naturally may be a standard strike.

Those persons skilled in the art will appreciate that my thin plate-like trigger bolt 17 will take up little room on the lock casing 10. Moreover, I can utilize that trigger bolt when the lock casing 10 is a standard casing with its front opening 18 of a certain size. Thus, it will merely be necessary to reduce slightly the size of the latchbolt 13 to enable trigger bolts 17 to be arranged with the latchbolt in the same front opening 18. Alternately, it will suffice to make a front opening very slightly larger, in those locks in which that may be possible. When trigger bolt 17 is in retracted position, its end portion 26 will overlie a part of the front 14 of casing 10, and the front opening 18 need not be designed to accept that end portion 26. If it is found desirable that trigger bolt 17 move to a more retracted position, the lock casing 10 merely need be somewhat relieved as shown at 28, so :as to accept the end portion 26.

Referring to FIGS. 2, 3 and 4, I utilize with the trigger bolt 17 a dogging plate 30 which is arranged in juxtaposed relation to an inner side of the lock casing 10. I mount the dogging plate 36 to pivot on a cross member 31 on casing 16 the plate 31) extending in a forward direction toward the circumferential sides of the latchbolt 13 and the trigger bolt 17, and being pressed by a spring 32 toward those bolts. As best shown in FIGS. 2, 5 and 6, the dogging plate 30 is formed at its front end with boltcoacting portions 33, 34 that are in aligned relation to trigger bolts 17 and to latchbolt 13. A further porion 35 is aligned relatively to a bolt retracting link 36.

The circumferential side of trigger bolt 17 has at its rear end a cam surface 37, best seen in FIG. 6, which coacts with the portion 33 on dogging plate 30 to hold that plate in a release position when trigger bolt 17 is projected. When trigger bolt 17 is retracted through contact with the strike surface 27, as in FIG. 4, cam surface 37 will move rearwardly, allowing spring 32 to move dogging plate 30 to a dogging position. In that dogging position, the plate portion 34 is behind a surface 38 on the latchbolt 13, deadlatching latchbolt 13 so that it cannot be pressed to retracted position.

I form the bolt retracting link 36 with a cam portion 39 that coacts with the portion 35 on dogging plate 36, so that when moving to retract latchbolt 13, the link 36 will move plate 39 to release position, enabling latchbolt 13 to be retracted through knob operation.

When considering FIGS. 3 and 4, it will be seen that the dogging plate 30 actually need move only a very short distance between its dogging and release positions. Therefore, plate 30 will merely require for its operation a small amount of space juxtaposed to the inner side of casing 19.

I have referred to merely one latchbolt retracting link 36 because that link coacts with dogging plate 30, but the construction I illustrate actually has a pair of links, best seen in FIG. 6, including link 36 and a further link 36a. As in Patent No. 3,115,357, the front end of retracting links 36, 36a is connected through a pivot pin 40 to the latchbolt 13, links 36 and 36a are each provided with elongated openings 36b a rearward portion of those links being movable in openings in the cross member 31 and connected through a pivot pin 41 to a bolt retractor 42, FIGS. 2 to 5. Elongated openings 36!) allow some lost motion between the retractor 42 and bolt 13 permitting cam 37 to disengage dogging plate 30 from bolt 13 as the door knob 11 is rotated to open the door. To press latchbolt 13 toward projected position, I utilize a coil spring 43, FIG. 6, arranged longitudinally between retracting links 36, 36a. The forward end of spring 43 acts through an enlarged portion 44 against the pivot pin 40 on latchbolt 13, While the rear end of spring 43 acts through a spring guide 45 against cross member 31.

Referring now to FIGS. 2 and 5, the deadbolt 16 is operated through a cam member and a retracting plate 59 which are like those shown in the application to which I have referred. Cam member 50 is arranged in position behind the deadbolt 16 and latchbolt 13, and iS mounted on a stem 51 on finger piece 15, so as to be rotated by the finger piece. A part of cam member 50 engages a slot 52 in a rear portion of deadbolt 16, and will act between a pin 53 and the forward end of slot 52 to project and retract deadbolt 16. When in bolt projecting position, as in FIG. 5, cam member 50 will act through .a surface 54 to dog deadbolt 16, while a further surface 55 will lie in opposed relation to a part of latchbolt 13, deadlocking that bolt. A curved spring 56 acts between the cross member 31 and surfaces 57, 58 on cam member 50 for holding that member in its bolt retracting and release positions.

Retracting plate 59 is connected to the pin 41 on bolt retractor 42, and has a forward end portion 60 adapted to act against a lug 61 on cam member 50. When the bolt retractor 42 moves to retract latchbolt 13, it first will slide the retracting plate 59 in a rearward direction so as to rotate cam member 50 to release position, if member 50 is not already in that position. Thus, when a person wishes to open the door and rotates the inside knob, the knob will act automatically to undog the latchbolt 13, and to retract the deadbolt as well as the latchbolt.

I believe it will be unnecessary to describe the details of the bolt retractor 42 and the means through which that retractor is operated, since those details are not important to an understanding of my present invention. It is merely necessary to know here that the rotation of an inside knob 11 will slide bolt retractor 42 in a rearward direction against the pressure of retractor springs 62, whereby to move the retracting links 36, 36a and the retracting plate 59.

From the description that I have made, it will be appreciataed that the novel concept of my invention enables me to achieve automatic deadlatching, while also utilizing manual means for dogging a deadbolt and latchbolt. In effect, I achieve double deadlocking of a latchbolt.

The exceedingly novel deadlatching mechanism of my invention will take up but little room on a lock casing, and can very well be utilized on a lock that has a very small amount of available space. In fact, the trigger bolt may be mounted within the outlines of the same opening as is the latchbolt, simply through a slight reduction in the size of the latchbolt. It is then possible to use a standard lock casing, as well as further lock parts that are standard in most respects. That naturally will facilitate the manufacture of a series of locks in which there is a lock With a deadlatching function, and a lock without that function. I achieve these things while contributing deadlatching mechanism that will operate extremely well. I believe, therefore, that the very considerable value of my invention will be understood, and that the merits of my invention will be fully appreciated by those skilled in the art.

I now claim:

1. In a lock of the class described, a casing, inner and outer actuating handles, a latchbolt movable in an opening in the front of said casing and spring pressed to a. projected position for entering an opening in a strike, a plate-like trigger bolt pivotally mounted in said front opening on said casing in juxtaposed relation. to a. surface of the latchbolt and pressed toward a projected position aligned relatively to the front opening of the casing, the pivotal mounting and shape of said plate-like trigger bolt being such that the strike pivots the trigger bolt into a retracted position wherein a part of said trigger bolt lies laterally outside the front opening when a door equipped with said lock moves to closed position to allow the latchbolt to enter said strike opening, first means releasably controlled by the trigger bolt in said casing for dogging the latchbolt in projected position when the trigger bolt is so retracted by the strike, second means for dogging said latchbolt in said projected position and means for automatically undogging said first and second dogging means upon turning of said inner actuating handle.

2. In a lock of the class described, a casing, inner and outer actuating handles, a latchbolt movable in an opening in the front of said casing and spring pressed to a projected position for entering an opening in a strike, a plate-like trigger bolt pivotally mounted in said front opening of the casing in juxtaposed relation to a surface of the latchbolt and pressed toward a projected position aligned relatively to the front opening of the casing, said plate-like trigger bolt having a forward surface so inclined that the strike pivots the trigger bolt into a retracted position when a door equipped with said lock moves to closed position to allow the latchbolt to enter the opening of said strike, an end portion of the trigger bolt extending in a direction to lie laterally outside the front opening so that the strike will hold said trigger bolt retracted when the latchbolt enters the strike opening, first means releasably controlled by the trigger bolt in said casing for dogging the latchbolt in projected position when the trigger bolt is so held retracted by the strike, second means for dogging said latchbolt in said projected position, and means for simultaneously undogging said first and second dogging means upon turning of said inner actuating handle.

3. In a lock of the class described, a casing, inner and outer actuating handles, a latchbolt movable in an opening in the front of said casing and spring pressed to a projected position for entering an opening in a strike, a thin plate-like trigger bolt movable in said front opening of said casing in juxtaposed relation to the bottom surface of the latchbolt and pressed toward a projected position aligned relatively to the front opening of the casing, an inclined forward surface of said thin plate-like trigger bolt engaged by the strike so that the strike moves the trigger bolt into a retracted position when a door equipped with said lock moves toward closed position, an end part of the thin plate-like trigger bolt extending laterally beyond a side of the latchbolt so as to lie outside the front opening when the door is in closed position, said strike coacting with said end part to hold the trigger bolt retracted while the latchbolt enters the strike opening, first means releasably controlled by the trigger bolt in said casing for dogging the latchbolt in projected position when the trigger bolt is so held retracted by the strike, second means for dogging said latchbolt in said projected position, and means for simultaneously undogging said first and second dogging means upon turning of said inner actuating handle.

4. In a lock of the class described, a casing, a latchbolt pivoted to rotate in an opening in the front of said casing and spring pressed to a projected position for entering an opening in a strike, said latchbolt having a curved side coacting with the strike when the latchbolt is in the strike opening, a thin plate-like trigger bolt pivotally mounted in juxtaposed relation to the bottom surface of the latchbolt in said front opening of the casing and pressed toward a projected position alignment with said front opening, a radially extending forward surface of said thin plate-like trigger bolt engaged by a surface of the strike so that the strike rotates the trigger bolt into a retracted position when a door equipped with said lock moves toward closed position, an end part of the thin plate-like trigger bolt extending in a radial direction beyond the curved side of the latchbolt so as to lie against said surface of the strike when the door is in closed position, said strike surface coacting with said end part to hold the trigger bolt retracted while the latchbolt enters the strike opening, first means releasably controlled by the trigger bolt in said casing for dogging the latchbolt in projected position when the trigger bolt is so held retracted by the strike, second means for dogging said latchbolt, and means for automatically undogging said first and second dogging means when said inner ac tuating handle is rotated.

5. In a lock of the class described, a casing, inner and outer actuating handles, a deadbolt movable between projected and retracted position relatively to said casing, a spring pressed latchbolt arranged below said deadbolt and mounted for movement between projected and retracted positions relatively to said casing, a manually actuated cam member mounted in position behind the deadbolt and latchbolt in the casing, means whereby said cam member when actuated projects the deadbolt and deadlocks both the deadbolt and latchbolt in projected positions, a thin plate-like trigger bolt juxtaposed to the bottom surface of the latchbolt and mounted to project and retract independently of the latchbolt on the casing, a portion of said thin trigger bolt extending laterally beyond a side of the latchbolt in position to coact with a strike so that the strike will hold the trigger bolt retracted, a movable dogging plate juxtaposed to an inner side of the casing and substantially aligned with sides of the latch bolt and thin trigger bolt, and a cam portion on said trigger bolt for coacting with the dogging plate to releasably control a movement of said plate to a dogging position behind the latchbolt when the trigger bolt is retracted by the strike, allowing the latchbolt in effect to be double deadlocked through the operation of both the manual cam member and the trigger bolt, and means for automatically undogging said double deadlocking of said latchbolt upon turning of said inner actuating handle.

References Cited by the Examiner UNITED STATES PATENTS 938,921 11/1909 Voight -418 957,139 5/1910 Berry 70150 1,604,946 10/1926 Shaw 70151 3,115,357 12/1963 Kulick 2925 FOREIGN PATENTS 359,702 10/1931 Great Britain. 881,744 11/1961 Great Britain.

JOSEPH D. SEERS, Primary Examiner.

ALBERT H. KAMPE, M. HENSON WOOD, JR.,

Examiners. 

1. IN A LOCK OF THE CLASS DESCRIBED, A CASING, INNER AND OUTER ACTUATING HANDLES, A LATCHBOLT MOVABLE IN AN OPENING IN THE FRONT OF SAID CASING AND SPRING PRESSED TO A PROJECTED POSITION FOR ENTERING AN OPENING IN A STRIKE, A PLATE-LIKE TRIGGER BOLT PIVOTALLY MOUNTED IN SAID FRONT OPENING ON SAID CASING IN JUXTAPOSED RELATION TO A SURFACE OF THE LATCHBOLT AND PRESSED TOWARD A PROJECTED POSITION ALIGNED RELATIVELY TO THE FRONT OPENING OF THE CASING, THE PIVOTAL MOUNTING AND SHAPE OF SAID PLATE-LIKE TRIGGER BOLT BEING SUCH THAT THE STRIKE PIVOTS THE TRIGGER BOLT INTO A RETRACTED POSITION WHEREIN A PART OF SAID TRIGGER BOLT LIES LATERALLY OUTSIDE THE FRONT OPENING WHEN A DOOR EQUIPPED WITH SAID LOCK MOVES TO CLOSED POSITION TO ALLOW THE LATCHBOLT TO ENTER SAID STRIKE OPENING, FIRST MEANS RELEASABLY CONTROLLED BY THE TRIGGER BOLT IN SAID CASING FOR DOGGING THE LATCHBOLT IN PROJECTED POSITION WHEN THE TRIGGER BOLT IS SO RETRACTED BY THE STRIKE, SECOND MEANS FOR DOGGING SAID LATCHBOLT IN SAID PROJECTED POSITION AND MEANS FOR AUTOMATICALLY UNDOGGING SAID FIRST AND SECOND DOGGING. MEANS UPON TURNING OF SAID INNER ACTUATING HANDLE. 